Epiphytic plants – Air plants – no soil plants

As gardeners, most of us are fully accustomed to growing plants in containers or directly in the ground, but for some who lack the generosity of garden space, growing plants can often be a struggle with space restrictions, difficult corners to tackle or an overabundance of tree cover to block out sunlight. Well what may seem like obstacles should possibly be viewed as wonderful opportunities to embrace a special group of plants that are highly adapted to take full advantage of these situations, the epiphytes.

Epiphytic plants are scattered around the globe from wet tropical regions to dry arid zones and have managed to colonise natural spaces where many other plant species can often struggle to get a foothold.

Where most plants form roots to take up nutrition and moisture from the soil, the roots systems of epiphytes are specially developed to also hold them firmly in place in the bows or trunks oftrees, on fallen logs, and in some cases, directly on the hard surfaces of rocks and other debris. They have developed specialized tactics in which to extract moisture and nutrition sources unlike most other plants and this provides them with a clear advantage when faced with extreme weather conditions.

Here are a few easy to grow species that you may like to enjoy in your garden.

Ferns

There are many species of Birds nest ferns (Asplenium species) most of which are native to Australia. They can be naturally found high up in the canopy of trees in rainforests snuggled in between the branches where their majestic deep green shiny fronds are held out wide to capture the dappled sunlight and falling debris. Some may also be found growing closer to the ground on fallen logs in between other, smaller ferns species and occasionally can be seen growing right at ground level within decaying organic matter. Their distinctive shape is deliberate as the wide green fronds capture falling leaf litter from the surrounding trees within the heart of the plant. Over time, this debris naturally degrades and becomes an invaluable source of nutrition for the plants. They all have a strong network of tiny roots that anchor them firmly in place and are able to withstand high wind. For those gardeners with a keen eye for the aesthetic quality of plants, avoid being tempted to clear the heart of Aspleniums as this is vitally important for the development of new fronds. But avoid deliberately filling it up too much with waste as this can inhibit growth.

Another fern species most will be familiar with are the Staghorn Fern (Platycerium grande) and the Elkhorn fern (Platycerium bifurcatum). Again both are native to Australia and have been well embraced by gardeners around the country. Unlike the birds nest ferns, these species grow directly on the trunks of trees and palms as long as they can get a firm footing. It takes time for these epiphytic fern species to become fully secure in their natural positions so when purchased from garden centres, they are often found already mounted on a backing board to make this easier. They naturally live off decaying organic matter that has landed within their backing shields yet the Platyceriums enjoy a small boost of potassium in their diet. This can easily be achieved by placing a banana skin down the back of the shield once every six months.

Staghorn & Elkhorn

Birds nest, Stag & Elkhorns enjoy growing conditions, sheltered away from the intensity of thesun, yet in a bright position. Watering should be done frequently in extremely hot weather and kept to a minimum during the colder parts of the year.

Spot the difference!

Elkhorn ferns grow in thick colonies that form the look of one enormous (rounded) plant with multiple smaller fronds in all directions, while the Staghorn has upward facing fronds that form a “shield” and two main fertile fronds hanging vertically downwards.

Bromeliads

When you mention the word Bromeliad to most people, they often imagine them massed planted under trees as a terrestrial planting option or in designer pots on the balcony or veranda, yet most are naturally epiphytic by nature and can be found scaling large trees in attractive coloniesmade up of many hundreds of plants. Many of the smaller, clumping varieties such as the Neoregelia species are extremely adapted to growing in this way and can be easily attached to the trunks of a tree or even to the sides of sturdy hanging baskets for extra effect. Most multiply quickly and develop attractive bright colours and markings depending on the time of year. The root systems of these bromeliads are relatively tiny, yet are incredibly strong as the plants gradually ‘march’ their way up a tree trunk. Watering isn’t a major issue as by ensuring that moisture is kept within the centre of each bromeliad it can be easily sustained.

Orchids

Many of our much-loved orchids such as Cattleya, Vanda and Oncidium species that are commonly purchased in pots make excellent options to be used alongside many other epiphytic plants. In fact most naturally grow in soilless environments where their fleshy roots adhere tightly to the trunks and bows of trees or are lightly covered in fallen organic debris from which they obtain a regular supply of nutrition. Orchids come from all parts of the world and can often be best enjoyed when encouraged to grow in their natural environment for best effect. Most native species orchids, such as the many dendrobium species, will eagerly climb their way along branches while forms, such as the Oncidium (Dancing Ladies), will form large healthy clumps that flower at the end of spring each year with an eruption of weeping spikes in bright yellow, orange and red flowers. They can be divided every few years for easy propagation and placed in other parts of the garden or potted up and given away as gifts. Orchids can easily be used in open hanging basket situations when planted into a specialty orchid mix and hung directly from tree limbs or balconies and verandas for an extra beautiful feature for everyone to enjoy. In their native tropical environments, minute particles of debris act as fertiliser, yet in a garden environment, the addition of a small amount of liquid or slow release fertiliser every three or four months will provide enough nutrition throughout the year.Most orchids prefer a protected site with bright light, yet Oncidium orchids also have the ability to grow and flower well in full sun.

Tillandsias

Tillandsias are a first cousin to the bromeliads that are mostly grown and are true ‘air plants’. There are many forms in cultivation and most produce brightly coloured appealing blooms on delicate flower spikes directly from the centre of each plant. These are extremely easy to grow and can be simply attached to pieces of wood and hung in position or even in a vertical wall situation combined with orchids and other small bromeliads. Fully adaptable to both full sun and light shade, Tillandsias truly bring strong fascination to a garden scene and are highly popular with the younger generation for their novel appearance. The most well-known of all species is the old fashioned ‘Old Man’s beard’ (Tillandsia usneoides) with its attractive silver grey fine foliage cascading over low branches or wooden fences. This form is eagerly utilised by many smaller bird species that use it as nesting material and in turn unwittingly spread this species to many neighbouring branches of trees and shrubs.

Grouping many different species of tillandsias together on fallen tree branches along with small orchids is one definite way of making an outstanding feature in any sized garden.In nature, tillandsias capture heavy dew on their fine foliage so do not require heavy watering to survive. During the heat of summer, simply splashing water over the plants is more than enough to ensure a gradual colonisation to occur.

Hoyas

Often seen in hanging baskets, an unlikely addition to the epiphyte world is the Hoya. These climbing plants produce aerial roots that also adhere to their host tree and can make interesting and easy care plants for the garden. Australia can claim a few species of hoya (H.australis) to this wide and varied family that produce tight clusters of honey scented blooms. They detest being wet for long periods and are highly adaptable to most environments.

Most epiphytic plants require little or no care as far as insect or disease control is concerned minimising the need for spraying harsh chemicals in and around the home. Unlike most potted plants that require attention, they strengthen peace of mind if you happen to be away from the garden for extended periods as they will undoubtedly look as healthy on your return as when you left.